Field of the Invention
The present invention relates to a floor member including a floor portion of a cab provided in a working machine, and a working machine provided with the floor member.
Description of the Background Art
Conventionally, there is known a construction machine provided with a lower traveling body, an upper slewing body including a slewing frame slewably mounted on the lower traveling body, and a cab loaded on the slewing frame and to be operated by an operator (see e.g. Japanese Unexamined Patent Publication No. 2006-56325). In the construction machine, the cab includes a rectangular floor plate extending in a front-rear direction of the cab, a cab box loaded on the floor plate, and four mount members directly attached to the back surface of the floor plate in such a manner as to respectively overlap the four corner portions of the floor plate. The floor plate and the cab box are supported on the slewing frame of the upper slewing body via the four mount members.
The cab of the construction machine further includes a pair of left and right reinforcement members joined to the back surface of the floor plate in order to prevent vibrations by flexure of the floor plate. Each of the reinforcement members extends in the length direction along the front-rear direction of the cab, but is disposed in a region between each two mount members located on the front side and on the rear side in the length direction so as to avoid interference with the mount members attached to the corner portions of the floor plate. Specifically, each of the reinforcement members is disposed at a lengthwise middle portion of the floor plate. Each of the reinforcement members is aligned with the corresponding two mount members located on the front side and on the rear side of the floor plate in the length direction, but is distanced away from the corresponding two mount members.
In the construction machine, the floor plate has a rectangular shape extending in a front-rear direction of the cab, and the four corner portions of the floor plate are supported on the slewing frame via the mount members. In this configuration, the lengthwise middle portion of the floor plate may be flexed when a heavy load is loaded on the lengthwise middle portion of the floor plate. In order to prevent such a flexure, there is proposed an idea of increasing the thickness of the floor plate or increasing the thickness of the reinforcement members disposed at the middle portion of the floor plate. However, this may unavoidably increase the entire weight and cost of the floor plate and of the reinforcement members.